Dec 23 2008
Using the same type of nanotechnology that enables hard drives to read and write data, researchers at Stanford University have developed a system that should be able to detect cancer in the human body. The blood scanner, which is still in the prototype stage, is designed to find cancer markers in the blood stream in the early stages of the disease, when they can be treated more easily and successfully, according to Stanford University. The research document also noted that the sensors can detect cancer markers in a blood sample in less than an hour.
"This is essentially a proof-of-concept study showing that now we have a chip and a reader that can find multiple biomarkers in a sample at a concentration much lower than the standard that is commercially available," said Shan Wang, a Stanford professor of materials science and electrical engineering, in a statement. "The earlier you can detect a cancer, the better chance you have to kill it. This could be especially helpful for lung cancer, ovarian cancer and pancreatic cancer, because those cancers are hidden in the body."
According to the university, the scanner is based on a silicon chip that has 64 embedded sensors. A handheld device holds the chip, which can detect changes in magnetic fields. Captured cancer proteins are tethered to magnetic nanoparticles. When the sensors detect the magnetic particles, they've also found the cancer markers.
Traditional scanners use electrically charged or glowing particles instead of magnetic nanoparticles. Since magnetism is rarely found in biological systems, researchers noted that they tend to stand out "like a flare in the night sky". The report added, "By tagging cancer proteins with tiny magnetic particles, rather than electrically charged or glowing particles as in other detectors, the new system can obtain a clearer signal from a smaller number of cancer proteins."
Using nanotechnology to fight cancer is an idea that has been growing. In August, researchers at Stanford announced that they had found a way to use nanotechnology to have chemotherapy drugs target only cancer cells, keeping healthy tissue safe from the treatment's toxic effects.
Cancer researchers have been trying to figure out a way to better deliver drugs to cancer cells without blasting surrounding cells as well. The Stanford research developed a way to use single-walled carbon nanotubes as targeted medicinal delivery vehicles.
In July, scientists at the University of California, San Diego said they had discovered a way to use nanotechnology-based "smart bombs" to streamline lower doses of chemotherapy to cancerous tumors, cutting down on the cancer's ability to spread through the body.
Scientists reported that a nanoparticle, carrying a payload of chemotherapy, targets a protein marker found on the surface of certain tumor blood vessels that are associated with the development of new blood vessels and malignant tumor growth.
And last week, scientists at MIT announced that they had developed nanotechnology that can be placed inside living cells to determine whether chemotherapy drugs are reaching their targets or attacking healthy cells.
The sensors, which can detect chemotherapy drugs as well as toxins and free radicals, are carbon nanotubes that scientists have wrapped in DNA so they can be safely injected into living tissue, according to a release from the university.
In this week's announcement, Stanford noted that the new nanotechnology research is tens to hundreds of times more sensitive than traditional cancer scanning techniques.
"This work represents a giant leap... with significant potential for many applications including cancer detection and management," said Dr. Sam Gambhir, the principal investigator of the Center of Cancer Nanotechnology Excellence at Stanford, in a written statement.